In relation to the amount of civil penalties that can be accessed per day.

No definition available.

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Namespace Prefix:	bdco_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The amount of litigation reserve that was reversed.

+ References

No definition available.

+ Details

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- Definition

The carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 410
-SubTopic 20
-Name Accounting Standards Codification
-Section 25
-Paragraph 4
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481999/410-20-25-4

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 410
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481850/410-20-50-1

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of asset retirement obligations incurred during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 410
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (c)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481850/410-20-50-1

+ Details

Name:	us-gaap_AssetRetirementObligationLiabilitiesIncurred
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of asset retirement obligations settled, or otherwise disposed of, during the period. This may include asset retirement obligations transferred to third parties associated with the sale of a long-lived asset.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 410
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (c)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481850/410-20-50-1

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Aggregate carrying amount of the estimated litigation liability for known or estimated probable loss from litigation, which may include attorneys' fees and other litigation costs.

+ References

+ Details

Name:	us-gaap_LitigationReserve
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The value (monetary amount) of the award the plaintiff seeks in the legal matter.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 450
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483076/450-20-50-1

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 450
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483076/450-20-50-4

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 450
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483076/450-20-50-9

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

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Namespace Prefix:
Data Type:	na
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- Details

Name:	srt_CounterpartyNameAxis=bdco_BureauOfSafetyAndEnvironmentalEnforcementBseeMember
Namespace Prefix:
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Balance Type:
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- Details

Name:	srt_LitigationCaseAxis=bdco_BseeCivilPenaltyG2024054Member
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- Details

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Namespace Prefix:
Data Type:	na
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- Details

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- Details

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Note 10 - AROs (Details Textual) - USD ($)		1 Months Ended		3 Months Ended	6 Months Ended	12 Months Ended	13 Months Ended
Note 10 - AROs (Details Textual) - USD ($)	Jul. 21, 2025	Mar. 31, 2025	Jan. 31, 2025	Mar. 31, 2024	Jun. 30, 2025	Dec. 31, 2024	Jan. 31, 2025	Sep. 30, 2025	Dec. 31, 2023
Asset Retirement Obligation						$ 2,999,000			$ 4,504,000
Asset Retirement Obligation, Liabilities Settled					$ 2,999,000	2,999,000
Blue Dolphin Pipe Line Company (BDPL) [Member]
Asset Retirement Obligation					3,000,000	$ 3,000,000
Asset Retirement Obligation, Liabilities Settled				$ 1,500,000
Asset Retirement Obligation, Liabilities Incurred				$ 900,000
Blue Dolphin Pipe Line Company (BDPL) [Member] \| Bureau of Safety and Environmental Enforcement (BSEE) [Member]
Estimated Litigation Liability					2,100,000
Blue Dolphin Pipe Line Company (BDPL) [Member] \| Bureau of Safety and Environmental Enforcement (BSEE) [Member] \| BSEE Civil Penalty G2024054 [Member]
Loss Contingency, Damages Sought, Value		$ 1,000,000
Civil Penalties Per Day		3,097
Blue Dolphin Pipe Line Company (BDPL) [Member] \| Bureau of Safety and Environmental Enforcement (BSEE) [Member] \| BSEE Civil Penalty G2024054 [Member] \| Subsequent Event [Member]
Loss Contingency, Damages Sought, Value	$ 1,300,000
Blue Dolphin Pipe Line Company (BDPL) [Member] \| Bureau of Safety and Environmental Enforcement (BSEE) [Member] \| BSEE Civil Penalty G2024056 [Member]
Loss Contingency, Damages Sought, Value			$ 400,000				$ 400,000
Civil Penalties Per Day			$ 3,097				$ 3,097
Blue Dolphin Pipe Line Company (BDPL) [Member] \| Bureau of Safety and Environmental Enforcement (BSEE) [Member] \| BSEE Civil Penalty G2024056 [Member] \| Forecast [Member]
Estimated Litigation Liability								$ 300,000
Blue Dolphin Pipe Line Company (BDPL) [Member] \| Bureau of Safety and Environmental Enforcement (BSEE) [Member] \| BSEE Civil Penalty G2024056 [Member] \| Subsequent Event [Member]
Loss Contingency, Damages Sought, Value	900,000
Civil Penalties Per Day	$ 3.097
Blue Dolphin Pipe Line Company (BDPL) [Member] \| Bureau of Safety and Environmental Enforcement (BSEE) [Member] \| BSEE Civil Penalty G2024010 [Member]
Loss Contingency, Damages Sought, Value		1,100,000
Estimated Litigation Liability		$ 1,100,000
Reversal of Litigation Reserve					$ 1,100,000